[linux-2.6-block.git] / fs / cifs / cache.c

/*
 *   fs/cifs/cache.c - CIFS filesystem cache index structure definitions
 *
 *   Copyright (c) 2010 Novell, Inc.
 *   Authors(s): Suresh Jayaraman (sjayaraman@suse.de>
 *
 *   This library is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU Lesser General Public License as published
 *   by the Free Software Foundation; either version 2.1 of the License, or
 *   (at your option) any later version.
 *
 *   This library is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
 *   the GNU Lesser General Public License for more details.
 *
 *   You should have received a copy of the GNU Lesser General Public License
 *   along with this library; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
#include "fscache.h"
#include "cifs_debug.h"

/*
 * CIFS filesystem definition for FS-Cache
 */
struct fscache_netfs cifs_fscache_netfs = {
	.name = "cifs",
	.version = 0,
};

/*
 * Register CIFS for caching with FS-Cache
 */
int cifs_fscache_register(void)
{
	return fscache_register_netfs(&cifs_fscache_netfs);
}

/*
 * Unregister CIFS for caching
 */
void cifs_fscache_unregister(void)
{
	fscache_unregister_netfs(&cifs_fscache_netfs);
}

/*
 * Server object for FS-Cache
 */
const struct fscache_cookie_def cifs_fscache_server_index_def = {
	.name = "CIFS.server",
	.type = FSCACHE_COOKIE_TYPE_INDEX,
};

/*
 * Auxiliary data attached to CIFS superblock within the cache
 */
struct cifs_fscache_super_auxdata {
	u64	resource_id;		/* unique server resource id */
};

char *extract_sharename(const char *treename)
{
	const char *src;
	char *delim, *dst;
	int len;

	/* skip double chars at the beginning */
	src = treename + 2;

	/* share name is always preceded by '\\' now */
	delim = strchr(src, '\\');
	if (!delim)
		return ERR_PTR(-EINVAL);
	delim++;
	len = strlen(delim);

	/* caller has to free the memory */
	dst = kstrndup(delim, len, GFP_KERNEL);
	if (!dst)
		return ERR_PTR(-ENOMEM);

	return dst;
}

static enum
fscache_checkaux cifs_fscache_super_check_aux(void *cookie_netfs_data,
					      const void *data,
					      uint16_t datalen,
					      loff_t object_size)
{
	struct cifs_fscache_super_auxdata auxdata;
	const struct cifs_tcon *tcon = cookie_netfs_data;

	if (datalen != sizeof(auxdata))
		return FSCACHE_CHECKAUX_OBSOLETE;

	memset(&auxdata, 0, sizeof(auxdata));
	auxdata.resource_id = tcon->resource_id;

	if (memcmp(data, &auxdata, datalen) != 0)
		return FSCACHE_CHECKAUX_OBSOLETE;

	return FSCACHE_CHECKAUX_OKAY;
}

/*
 * Superblock object for FS-Cache
 */
const struct fscache_cookie_def cifs_fscache_super_index_def = {
	.name = "CIFS.super",
	.type = FSCACHE_COOKIE_TYPE_INDEX,
	.check_aux = cifs_fscache_super_check_aux,
};

static enum
fscache_checkaux cifs_fscache_inode_check_aux(void *cookie_netfs_data,
					      const void *data,
					      uint16_t datalen,
					      loff_t object_size)
{
	struct cifs_fscache_inode_auxdata auxdata;
	struct cifsInodeInfo *cifsi = cookie_netfs_data;

	if (datalen != sizeof(auxdata))
		return FSCACHE_CHECKAUX_OBSOLETE;

	memset(&auxdata, 0, sizeof(auxdata));
	auxdata.eof = cifsi->server_eof;
	auxdata.last_write_time_sec = cifsi->vfs_inode.i_mtime.tv_sec;
	auxdata.last_change_time_sec = cifsi->vfs_inode.i_ctime.tv_sec;
	auxdata.last_write_time_nsec = cifsi->vfs_inode.i_mtime.tv_nsec;
	auxdata.last_change_time_nsec = cifsi->vfs_inode.i_ctime.tv_nsec;

	if (memcmp(data, &auxdata, datalen) != 0)
		return FSCACHE_CHECKAUX_OBSOLETE;

	return FSCACHE_CHECKAUX_OKAY;
}

const struct fscache_cookie_def cifs_fscache_inode_object_def = {
	.name		= "CIFS.uniqueid",
	.type		= FSCACHE_COOKIE_TYPE_DATAFILE,
	.check_aux	= cifs_fscache_inode_check_aux,
};
Commit	Line	Data
f579cf3c SJ	1	/*
	2	* fs/cifs/cache.c - CIFS filesystem cache index structure definitions
	3	*
	4	* Copyright (c) 2010 Novell, Inc.
	5	* Authors(s): Suresh Jayaraman (sjayaraman@suse.de>
	6	*
	7	* This library is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU Lesser General Public License as published
	9	* by the Free Software Foundation; either version 2.1 of the License, or
	10	* (at your option) any later version.
	11	*
	12	* This library is distributed in the hope that it will be useful,
	13	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
	15	* the GNU Lesser General Public License for more details.
	16	*
	17	* You should have received a copy of the GNU Lesser General Public License
	18	* along with this library; if not, write to the Free Software
	19	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	20	*/
	21	#include "fscache.h"
488f1d2d	22	#include "cifs_debug.h"
f579cf3c SJ	23
	24	/*
	25	* CIFS filesystem definition for FS-Cache
	26	*/
	27	struct fscache_netfs cifs_fscache_netfs = {
	28	.name = "cifs",
	29	.version = 0,
	30	};
	31
	32	/*
	33	* Register CIFS for caching with FS-Cache
	34	*/
	35	int cifs_fscache_register(void)
	36	{
	37	return fscache_register_netfs(&cifs_fscache_netfs);
	38	}
	39
	40	/*
	41	* Unregister CIFS for caching
	42	*/
	43	void cifs_fscache_unregister(void)
	44	{
	45	fscache_unregister_netfs(&cifs_fscache_netfs);
	46	}
	47
488f1d2d SJ	48	/*
	49	* Server object for FS-Cache
	50	*/
	51	const struct fscache_cookie_def cifs_fscache_server_index_def = {
	52	.name = "CIFS.server",
	53	.type = FSCACHE_COOKIE_TYPE_INDEX,
488f1d2d	54	};
d03382ce SJ	55
	56	/*
	57	* Auxiliary data attached to CIFS superblock within the cache
	58	*/
	59	struct cifs_fscache_super_auxdata {
	60	u64 resource_id; /* unique server resource id */
	61	};
	62
402cb8dd	63	char extract_sharename(const char treename)
d03382ce SJ	64	{
	65	const char *src;
	66	char delim, dst;
	67	int len;
	68
	69	/* skip double chars at the beginning */
	70	src = treename + 2;
	71
	72	/* share name is always preceded by '\\' now */
	73	delim = strchr(src, '\\');
	74	if (!delim)
	75	return ERR_PTR(-EINVAL);
	76	delim++;
	77	len = strlen(delim);
	78
	79	/* caller has to free the memory */
	80	dst = kstrndup(delim, len, GFP_KERNEL);
	81	if (!dst)
	82	return ERR_PTR(-ENOMEM);
	83
	84	return dst;
	85	}
	86
d03382ce SJ	87	static enum
	88	fscache_checkaux cifs_fscache_super_check_aux(void *cookie_netfs_data,
	89	const void *data,
ee1235a9 DH	90	uint16_t datalen,
ee1235a9 DH	91	loff_t object_size)
d03382ce SJ	92	{
d03382ce SJ	93	struct cifs_fscache_super_auxdata auxdata;
96daf2b0	94	const struct cifs_tcon *tcon = cookie_netfs_data;
d03382ce SJ	95
	96	if (datalen != sizeof(auxdata))
	97	return FSCACHE_CHECKAUX_OBSOLETE;
	98
	99	memset(&auxdata, 0, sizeof(auxdata));
	100	auxdata.resource_id = tcon->resource_id;
	101
	102	if (memcmp(data, &auxdata, datalen) != 0)
	103	return FSCACHE_CHECKAUX_OBSOLETE;
	104
	105	return FSCACHE_CHECKAUX_OKAY;
	106	}
	107
	108	/*
	109	* Superblock object for FS-Cache
	110	*/
	111	const struct fscache_cookie_def cifs_fscache_super_index_def = {
	112	.name = "CIFS.super",
	113	.type = FSCACHE_COOKIE_TYPE_INDEX,
d03382ce SJ	114	.check_aux = cifs_fscache_super_check_aux,
	115	};
	116
9451a9a5 SJ	117	static enum
	118	fscache_checkaux cifs_fscache_inode_check_aux(void *cookie_netfs_data,
	119	const void *data,
ee1235a9 DH	120	uint16_t datalen,
ee1235a9 DH	121	loff_t object_size)
9451a9a5 SJ	122	{
	123	struct cifs_fscache_inode_auxdata auxdata;
	124	struct cifsInodeInfo *cifsi = cookie_netfs_data;
	125
	126	if (datalen != sizeof(auxdata))
	127	return FSCACHE_CHECKAUX_OBSOLETE;
	128
	129	memset(&auxdata, 0, sizeof(auxdata));
	130	auxdata.eof = cifsi->server_eof;
cbedeadf AB	131	auxdata.last_write_time_sec = cifsi->vfs_inode.i_mtime.tv_sec;
	132	auxdata.last_change_time_sec = cifsi->vfs_inode.i_ctime.tv_sec;
	133	auxdata.last_write_time_nsec = cifsi->vfs_inode.i_mtime.tv_nsec;
	134	auxdata.last_change_time_nsec = cifsi->vfs_inode.i_ctime.tv_nsec;
9451a9a5 SJ	135
	136	if (memcmp(data, &auxdata, datalen) != 0)
	137	return FSCACHE_CHECKAUX_OBSOLETE;
	138
	139	return FSCACHE_CHECKAUX_OKAY;
	140	}
	141
	142	const struct fscache_cookie_def cifs_fscache_inode_object_def = {
	143	.name = "CIFS.uniqueid",
	144	.type = FSCACHE_COOKIE_TYPE_DATAFILE,
9451a9a5 SJ	145	.check_aux = cifs_fscache_inode_check_aux,
9451a9a5 SJ	146	};